Eating peanuts daily helps decrease blood pressure and cholesterol regardless of flavouring

It doesn’t matter if you like your peanuts plain, roasted, salted or flavoured with chili spices. New research shows that the health benefits of peanuts are independent of how the snack nuts might be flavoured or seasoned. Researchers at Purdue University led by Dr. Richard Mattes reported this month that seasonings/flavours on snack peanuts did not offset their nutritional benefits.¹ Linked to this, the investigators also explored “whether consumption of salted peanuts would elevate blood pressure, honey-roasted peanuts would elevate postprandial glycemia (blood sugar), and/or spicy peanuts would elevate cortisol concentrations (a marker for stress)”. This is particularly important as health professionals may be reluctant to recommend peanuts that have been salted, sugared or have added spicy flavours like chilli. The Purdue researchers showed there was no basis for any prejudice against peanuts flavoured with salt, sugar (honey) or spices.

A group of 151 apparently healthy men and women aged 18-50 completed the study. They were randomly assigned to treatment groups. Everyone in the study incorporated 42 grams of peanuts daily. Participants were free to eat whatever else they liked. The peanuts were pre-packaged and provided to participants in 14 gram portions. Blood samples were taken every four weeks and other health measurements were taken every two weeks.

What they found was that people at greater risk of cardiovascular disease because of elevated blood pressure, cholesterol or triglycerides, derived the greatest health benefit from eating the peanuts. Those starting the study with the highest blood pressure had the greatest reductions in diastolic rates and it was found that those consuming salted or unsalted peanuts had greater decreases than honey-roasted or spicy peanuts. Similarly, participants who began the trial with elevated serum triglyceride concentrations (blood fats) experienced greater decreases than did those with lower concentrations.

Some people might express concern about consumption of honey-roasted peanuts, but the researchers were clear that they did not see the added sugar as a negative factor for two reasons: the amount of added sugar was very small and there was a likelihood that eating the honey-roasted peanuts could displace other foods with much higher levels of added sugar and fewer nutrients. As they argued, “consumption of honey-roasted peanuts, the flavour with the greatest amount of added sugar, would contribute only an additional 6 grams sugar to the diet each day.”

This study adds to the findings in 2010 from Dr. Mattes’ laboratory at Purdue that fasting blood lipids and body weight were not affected by the form and processing of peanuts: plain and salted kernels and peanut butter had comparable positive health effects on these risk factors.²

As with previous positive research findings about peanuts, no one is saying that peanuts in isolation are a silver bullet solution to poor eating patterns, but it is clear that incorporating peanuts can be a significant first step towards eating more healthily. The message for peanut consumers from this latest work by Professor Mattes’ team is clear: “the flavourings assessed in this trial (salt, sugar, and capsaicin (chilli) did not negatively affect the health benefits of peanut ingestion.”

 

Source: American Peanut Council

¹ Jones JB et al. “A randomized trial on the effects of flavorings on the health benefits of daily peanut consumption” American Journal of Clinical Nutrition 2014; 99: 490-496 supported by a grant from the US Agency for International Development Peanut Collaborative Research Support Program

² McKiernan F et al. “Effects of peanut processing on body weight and fasting plasma lipids” British Journal of Nutrition 2010; 104:418-426